A student lifts a 2.1‑kg physics book to a height of 64 cm and then puts it down to its original position. Assume that the speed of the book remains constant during the entire process. The work done by the student while lifting the book up, W1 =  Units Select an answer W J kg m/s^2 m/s m no units required  . The work done by the gravity force while lifting the book up, W2 =  Units Select an answer W kg J m/s^2 m m/s no units required  . The work done by the student while putting the book down, W3 =  Units Select an answer m/s^2 J m/s m W kg no units required  .

A student lifts a 2.1‑kg physics book to a height of 64 cm and then puts it down to its original position. Assume that the speed of the book remains constant during the entire process.

The work done by the student while lifting the book up,

W₁ =  Units Select an answer W J kg m/s^2 m/s m no units required  .

The work done by the gravity force while lifting the book up,

W₂ =  Units Select an answer W kg J m/s^2 m m/s no units required  .

The work done by the student while putting the book down,

W₃ =  Units Select an answer m/s^2 J m/s m W kg no units required  .

The work done by the gravity force while putting the book down,

W₄ =  Units Select an answer W J m/s^2 m/s m kg no units required  .

If the book is lifted up in 1.25 seconds, how much power was developed by the student?

P =  Units Select an answer W m m/s^2 m/s J kg no units required  .